Rename MaximizeMode to TabletMode

ash/wm/tablet_mode/tablet_mode_backdrop_delegate_impl.h

 // Copyright 2017 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#ifndef ASH_WM_TABLET_MODE_TABLET_MODE_BACKDROP_DELEGATE_IMPL_H_
+#define ASH_WM_TABLET_MODE_TABLET_MODE_BACKDROP_DELEGATE_IMPL_H_
+
 #include "ash/wm/workspace/backdrop_delegate.h"
 
 #include "ash/ash_export.h"
 #include "base/macros.h"
 
 namespace ash {
 
 // A backdrop delegate for MaximizedMode, which always creates a backdrop.
 // This is also used in the WorkspaceLayoutManagerBackdropTest, hence
 // is public.
-class ASH_EXPORT MaximizeModeBackdropDelegateImpl : public BackdropDelegate {
+class ASH_EXPORT TabletModeBackdropDelegateImpl : public BackdropDelegate {
  public:
-  MaximizeModeBackdropDelegateImpl();
-  ~MaximizeModeBackdropDelegateImpl() override;
+  TabletModeBackdropDelegateImpl();
+  ~TabletModeBackdropDelegateImpl() override;
 
  protected:
   bool HasBackdrop(aura::Window* window) override;
 
  private:
-  DISALLOW_COPY_AND_ASSIGN(MaximizeModeBackdropDelegateImpl);
+  DISALLOW_COPY_AND_ASSIGN(TabletModeBackdropDelegateImpl);
 };
 
 }  // namespace ash
+
+#endif  // ASH_WM_TABLET_MODE_TABLET_MODE_BACKDROP_DELEGATE_IMPL_H_